Git and Github

Jeremy Springman

University of Pennsylvania

Global Development: Intermediate Topics in Politics, Policy, and Data

PSCI 3200 - Spring 2024

Git and Github

Resources

To learn more about using git with R, check out happygitwithr.com

Git Basics

Git is a version control program, so you can avoid…

analysis.R
analysis_v1.R
analysis_v2.R
analysis_v2_FINAL.R

Version control

Helps avoid devastating loss/failure
Tracks changes and allows users to view or restore older versions
Can be private or public

Git is a version control system that helps manage changes to data, code, and other documents necessary for data analysis. Fundamentally, git is about “version control”. Data analysis tasks are often long-term efforts. They usually require input from multiple people and many rounds of revisions and additions. Version control creates a detailed, permanent record of this process. This helps to avoid devastating loss/failure and allows by tracking changes and allows users to easily view (or restore) older versions. GitHub, on the other hand, is a web-based platform that hosts Git repositories. It also adds its own features, including graphical interfaces and features for managing projects. GitHub provides a central location where data analysts can publish their repositories and collaborate with others. GitHub also allows analysts to keep repositories private, if data is sensitive or proprietary.

Git Basics

Each project is a repository (repo)

Data and code for projects are stored in a repo folder
Repo is hosted remotely on github.com and locally as a folder on your harddrive
Make changes locally, record them as a commit, push them to the remote version
pull changes made by others from the remote version down to your local copy

Git revolves around folders called repositories (or repos). A Git repo is a virtual storage of your project, allowing you to save versions of your code and track changes made over time. It consists of all the project’s files and the entire revision history.

Data and code for individual projects are stored in a dedicated repo. The repo is hosted remotely on github.com and stored locally on your computer’s harddrive. Repos exist on your hard drive as a normal folder (usually within a larger folder that includes all active git repositories you are working on). Users make changes locally, record them as a “commit”, which is a record of any changes you have made, and “push” them to the remote version - Users can “pull” changes made by others from the remote version down to their local copy

Git Basics

Usage

Edit files using your preferred software (RStudio, VSCode, MS Word, etc.)
When you’re done, record the changes as a commit, push them to the remote version

Collaboration

Precise record of who makes changes
Simultaneous editing can cause challenges

Git Basics

Essential commands

git pull origin main
git add .
git commit -m "describe your changes or vent frustration"
git push origin main

Git Basics

Git can be complicated

Often used for sophisticated software development
Branches, conflicts, merges, rebase
Massive online community to guide new users

Creating a Github account

Create an account for yourself or your organization

Go to github.com
Click “Sign-up” (top right)
Pick a username (ex. jrspringman)
Follow the instructions

Installing git

Open the terminal/command prompt
Check if you have git installed

git --version

Installing git

If no, install git

Mac should offer to install it for you
Windows visit gitforwindows.org, click “Download”, then double-click the .exe

Installing git

Installing git

Optional: Override the default branch name (select ‘main’)

Installing git

Make sure that “Git from the command line and 3rd-party software” is selected

Installing git

Connect your GitHub account

Open the terminal and enter the code below
Replace "Your Name"and "yourname@email.edu" with your name/email used to sign up for GitHub
Run the code

git config --global user.name "Your_user_name"
git config --global user.email "youremail@email.edu"

Connect your GitHub account

Connect your GitHub account

Check that the configuration worked

git config --list

Connect your GitHub account

Install a git client

Visit desktop.github.com and click “Download”
Double click the .exe

Install a git client

Create a new repo

Sign-in to your account on github.com and click “New” in the top right

Create a new repo

Give your repository a name and decide whether to make it public or keep it private

Create a new repo

Clone your repo

Open the Github Desktop application and create a “clone” the remote repo to create a local copy

Clone your repo

Create a new repo

Commit changes

Now you can make changes to the repo, and those changes will appear as “diffs” in the application - Add a description and make a “commit” to record those changes in git

Push to your repo

Push those changes to the remote version of the repo on Github.com

Push to your repo

Pull from your repo

When colleagues push a commit to the repo, you can pull their commit by clicking “Pull origin”

Pull from your repo

Github Pages

Create a website

Moving to RStudio

File \(\rightarrow\) New Project \(\rightarrow\) New Directory \(\rightarrow\) Quarto Website

Create a website

Create a website

Change output director to docs

Publish to Github pages

Keep a repository of your website
Push changes to your website via Github
See changes almost instantly

Publish to Github pages

Open repo on github.com
Settings \(\rightarrow\) Pages (left-sidebar)

Publish to Github pages

Publish to Github pages

Publish to Github pages

Publish to Github pages

Publish to Github pages

Publish to Github pages

Host Your Final Project

Delete _site folder (now its using docs)
Create data folder to store your dataset
Add final project .qmd file to your repo (or drop it into index.qmd)
Use _quarto.yml to add new pages to navigation bar
Render index.qmd; confirm that other pages have been rendered
Push commit and check that the website updated